Matroids with at least two regular elements
نویسندگان
چکیده
For a matroid M , an element e such that both M \ e and M/e are regular is called a regular element of M . We determine completely the structure of non-regular matroids with at least two regular elements. Besides four small size matroids, all 3-connected matroids in the class can be pieced together from F7 or S8 and a regular matroid using 3-sums. This result takes a step toward solving a problem posed by Paul Seymour: find all 3-connected non-regular matroids with at least one regular element Oxley (1992) [5, 14.8.8]. © 2011 Elsevier Ltd. All rights reserved.
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ورودعنوان ژورنال:
- Eur. J. Comb.
دوره 33 شماره
صفحات -
تاریخ انتشار 2012